Optical switches can be utilized to redirect light beams in free space or between optical fibers. Many different types of optical switches fabricated by surface micromachining have been disclosed in recent years (see e.g. U.S. Pat. Nos. 5,867,302; 6,283,601; 6,366,414; 6,526,198; 6,535,318 and 6,545,385; see also L. Y. Lin et al, “Free-Space Micromachined Optical Switches for Optical Networking,” IEEE Journal of Selected Topics in Quantum Electronics, vol.5, pp. 4-9, 1999). The existing optical switches which are tiltable within a limited angular range generally suffer from a need to have electrical power applied at all times in order to establish and maintain an optical connection; whereas other of the existing optical switches which continue to operate when the electrical power is removed are generally limited to only a pair of well-defined angular states.
The microelectromechanical (MEM) optical switching apparatus of the present invention provides an advance over the prior art in being capable of redirecting an incident light beam over any angle within a wide angular range of up to 90° or more and can maintain a path for the redirected light beam after any applied electrical power has been removed. Furthermore, the MEM optical switching apparatus of the present invention can redirect an incident light beam to any of a plurality of optical fibers or to any of a plurality of angular directions in free space thereby forming a 1×N optical switch. The MEM optical switching apparatus of the present invention can also be formed as a 2×2 optical switch that operates using a single micromotor and with a plurality of mirrors in the 2×2 optical switch being moveable in unison.
These and other advantages of the present invention will become evident to those skilled in the art.